Gonbad

In traditional Persian architecture, a dome is referred to as a gonbad (Persian: گنبد‎‎).

The history of designing gonbads dates back to pre-Islamic Persia. The Parthians in particular were very keen in using such structures in their designs. The Sassanids inherited them and elevated their designs into full maturity.

A gonbad is often double layered, and can have many shapes, such as semi-spherical, partial spherical, onion shaped, paraboloid, polygonal conical, and circular conical.

In pre-Islamic times, the gonbad was a sign of imperial grandeur for the king. In Islamic times, the tradition continued, and the interiors were made to simulate the celestial dome, reminding the Muslim of Man's place in the cosmos compared to God and creation.

Kümbet is the name given to Seljuq mausoleums. Kümbet are an important part of Seljuq architecture. In Turkey, Azerbaijan and Iran where the Turks set up states and ruled for centuries, there are a number of examples of such mausoleums. Particularly fashionable in the thirteenth century, these monuments, referred to in Turkish as kümbet, are a continuation of the Turkish burial customs of Central Asia. These structures are either polygonal or cylindrical in shape arid are covered with a dome. The main body of the monument rests on a cubic base, the corners of which are bevelled. In the examples built before the 16th century, the dome is covered with a conical or pyramidal spire. Most of these monuments are two storied. Concealed inside the base, half of which is below ground level, is a crypt; the latter is covered by a vault and its floor is earth. The deceased was buried in the earth. The crypt had small loop-hole windows. Most kümbet in Turkey are found in the provinces of Kayseri, Erzurum, Konya, Ahlat and Bitlis

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